SMB 3.0 (previously named SMB 2.2) was introduced with Windows 8 and Windows Server 2012. It brought several significant changes, such as the SMB Direct Protocol (SMB over RDMA) and SMB Multichannel (multiple connections per SMB session), which are intended to add functionality and improve SMB2 performance, notably in virtualized data centers.

It does not sound terribly important for a home PC.

An interesting thing I learned from the article is that the principal performance problem was not SMB itself, but NetBIOS service location queries in NT 4.0 and later.

Overall I would say NFS is a miracle of networking. How it can be built on an unreliable protocol (UDP) and still be so reliable remains a mystery to me.